Scientists from Carnegie Mellon University (CMU) have discovered a way to produce a new material similar to hair strands, bristles and fibers, using a low-cost 3D printer.
The new technique was inspired by the way gossamer plastic strands extrude when a person fires a hot glue gun. The plastic hair is created strand by strand and it takes approximately 25 minutes for generating hair on 10 square millimeters. The hair strands can be produced by adding a simple set of parameters onto a 3D printer.
The resultant hair can be cut, curled and even braided. The dense, close-cropped strands can also be used to make a brush.
The research team used a fused deposition modeling (FDM) printer to create the hair strands. The nozzle extrudes small, flattened molten material strings into patterns until the necessary 3D shape is achieved. FDM printers are not so expensive – the one used by Carnegie Mellon costs about $300.
“You just squirt a little bit of material and pull away,” said Gierad Laput, a Ph.D student of Human-Computer Interaction Institute (HCII) at Carnegie Mellon. “It’s a very simple idea, really.”
To create the strands, the researchers applied a little bit of molten plastic and pulled the nozzle head away rapidly. A challenge in the process was that the print head was not designed to rise fast enough to generate the tapered strands.
The researchers tackled the issue by modifying the printing angle. Although the print head cannot move quickly, both the print head and bed can move sideways rapidly. By applying molten material and moving the print head and bed sideways, researchers realized that they could create hair-like strands, whichever way they wanted.
Laput and his colleagues added a variety of colors using the hair onto various 3D printed objects. Using randomized root positions, the team was able to produce natural-looking hair. Uniform root positions were used to produce toothbrush bristles.
The hairs were created using common materials, polylactide or PLA. Laput explained that using sophisticated materials like acrylonitrile butadiene styrene might enable the creation of hair strands with magnetic properties.
The hair strands can be used in a variety of industries such as pet care, cosmetics, toys and for other industrial applications. David and Lucile Packard Foundation, Yahoo! and Google supported the research.
Image and video courtesy of Carnegie Mellon University